1. Field of the Invention
The present invention relates to a method and to a device for at least partially closing off an open-top cavity of the pit or pool type, in particular for preventing anything falling into said cavity, and the present invention also relates to an installation, in particular a vehicle repair installation, of the type comprising at least a cavity and a device of the above-mentioned type for closing off the opening of the cavity.
2. Description of the Related Art
Such devices, designed to close off inspection or work pits of the type used by mechanics for repairing vehicles, are well known to persons skilled in the art.
Such a pit is constituted by a cavity in the general shape of a rectangular trough that is sunk into the floor and that is of width less than the widths of the vehicles to be repaired, so that said vehicles can be positioned over the pit along its longitudinal axis. While they are not being used, and for evident safety reasons, the openings of such pits should be closed off. This is usually achieved by laying a series of transverse beams or planks across said pits, with the respective edge faces of the beams or planks being laid against one another so as to form a continuous cover surface of the entire length of the pit.
Currently, in order enable that type of pit to be closed and opened automatically, each cover element is provided on its inside face with rack means suitable for co-operating with pinion means meshing with the rack means and controlled by actuator means. Such rack and pinion means make the resulting assembly complex and costly, as illustrated, for example, by patent FR-2 674 565.
It is also known that such a cover device can comprise at least one cover element for at least partially closing off the opening of the cavity and a support structure for supporting said cover element, which support structure is in the form of an elongate body for positioning the cover element in or close to the cavity, and preferably along one of the sides of the opening of said cavity. Said cover element is in the form of a pneumatic mattress equipped with return means for urging it back into a most compact configuration in which it is rolled up about a free one of its sides and forms a spirally wound roll, said free side about which the mattress is rolled up being formed by the side of the mattress that is opposite from the connecting side of the mattress via which side the mattress is connected to the support structure, said mattress being an inflatable mattress so that, by being rolled out, said mattress can go from its rolled-up most compact configuration, in which it is suitable for at least partially opening up the opening of said cavity, to a rolled-out least compact configuration in which it is suitable for at least partially closing the opening of the cavity.
In such cover devices, more particularly designed for covering over swimming pools, it is not possible, when the cover element is in its rolled-out least compact configuration, for said cover element to be used as a load-bearing floor, because of the design of the device.